Small union is causing big problems for ports

At a news conference Thursday, Berry denounced the tactics by the clerical workers, calling them "irresponsible."

Politicians, national retailers and others have weighed in, urging both sides to get back to the bargaining table. The National Retail Federation, representing many of the nation's big retail chains, has even asked President Obama to intercede to force both sides back to negotiations.

In 2002, President George W. Bush invoked the little used Taft-Hartley Act to end a 10-day lockout of dockworkers at all West Coast ports. That lockout cost the economy as much as $15 billion.

"An extended strike [in Los Angeles and Long Beach] this time could have a greater impact considering the fragile state of the U.S. economy," National Retail Federation Chief Executive Matthew Shay said in a letter to Obama. "The two sides must remain at the negotiating table until a deal is reached."

On Wednesday night, Los Angeles Mayor Antonio Villaraigosa added his voice in a letter to both sides.

"The city of Los Angeles needs both of you to get back to the bargaining table this week, to work with a mediator, and to hammer out a settlement before further harm is done to our local economy," Villaraigosa wrote. "There is no time to waste."

Economist Sung Won Sohn has a front-row seat on the dispute as a commissioner with Port of Los Angeles and vice chairman at retailer Forever 21, part of the fast-fashion industry that relies on frequent clothing imports to keep store offerings fresh.

"The last thing we need is a strike," said Sohn, an economist at Cal State University Channel Islands in Camarillo.

"I think it's incumbent upon the ports and labor unions to get together and resolve their differences as soon as possible. It's not just them who are affected, but really the entire nation."